The present invention relates to the use of an automatic spooling apparatus for continuous accumulation of flexible web or strip material such as a motion picture film. The present invention is intended to be used in conjunction with a source such as a film printing machine that prints a master picture negative and/or a master sound track onto a length of raw stock or unexposed film which is then fed to the automatic spooling apparatus for spooling or winding into rolls. The scope of the present invention incorporates both the apparatus for and the method of continuous accumulation of flexible web materials, for use with a film printing machine that exposes film either in air or in a liquid medium such as that disclosed in Carter et al U.S. Pat. No. 4,105,329.
During the process of high volume, high speed duplication of flexible web material such as motion picture film, it is necessary to have an apparatus which can efficiently wind and accumulate the flexible web materials in a roll fashion after it has passed through the duplication or film printing machine. Mechanisms currently in use to wind and accumulate such flexible web materials have definite limitations.
One frequently used method of winding printed photographic film is to provide alternate spooling or "take-up" spindles which are supplied with a flow of flexible web material. This requires stopping the printing machine at frequent intervals in order to manually break the flexible web at a predetermined point after one spool has been fully wound, and/or adding a new core in order to commence spooling of a new roll on the previously unloaded or empty spindle. This reduces the speed with which the film can be exposed and printed and reduces the output volume of finished product.
According to another method an interim accumulator, known in the film processing trade as "an elevator" is used to accumulate incoming film which is continuously being fed from the film printing machine while the operator stops the accumulating device to remove a fully wound spool and insert a fresh core to begin winding a new spool. The "elevator" or buffering apparatus is located between the flexible web printing machine and the flexible web accumulation and spooling mechanism. The "elevator" is voluminous in size and contains many rollers and other mechanical elements which require a large amount of maintenance to assure proper operation and a clean environment so that the exposed film will not be damaged. The higher the transport speed from the flexible web printing machine and the higher the winding rate of the flexible web spooling mechanism, the larger the capacity of the elevator or buffer that is required to permit the manual operations of breaking, respooling, and subsequent removal of the previous roll whether or not two or more take-up spindles are available.
The present invention overcomes many limitations of the existing systems and provides a significant improvement in the accumulation and spooling of flexible web materials during the process of high speed and high volume duplication of said flexible web materials. While the description in the specification relates to the use of motion picture film, the present invention is also applicable to any flexible web-type material such as microfilm, paper, vinyl, and the like. It is, therefore, a primary object of the present invention to provide a means for greatly improving the efficiency with which such flexible web material is accumulated and spooled.
A further object of the present invention is to provide an apparatus for efficiently winding and accumulating flexible web material after it has passed through a duplication or film printing machine.
Another object of the present invention is to reduce the manual labor required for removing filled spools of material and inserting empty spools and restarting the winding operation.
A further object of the present invention is to significantly reduce the total operator time required for removal of the fully wound flexible web spool and adding a new core and securing the flexible web material thereto prior to commencing the spooling of the next roll of flexible web material, thereby allowing a higher speed of printing or duplicating and providing a higher output volume of finished product.
A further object of the present invention is to provide an apparatus for efficiently and rapidly winding and accumulating the flexible web material wherein the operator need not be present to manually sever the flexible web at the desired point, and additionally need not be immediately present to remove the completed roll after it has been wound.
Yet another object of the present invention is to eliminate the need for the interim accumulator or "elevator" in use with existing spooling systems.
The major advantages of the present invention are most fully realized where high linear speeds of web material are used and therefore short periods of time are available to the operator for changeover from one spindle to the other, and removal of the previously wound roll.